Onetime nickname on the Yankees

AROD

This three-time MVP joined the Yankees in 2004 after making a name for himself as a star shortstop for the Mariners and Rangers.

This clue refers to Alex Rodriguez, the famous baseball player who spent years with the New York Yankees. "Onetime nickname" hints at his well-known initials-based moniker, "A-Rod," which combines his first initial and a shortened version of his last name. The answer is simply the letters pronounced as a word, dropping the hyphen for crossword style.